The present invention relates to machines for making wire mesh and, in particular, to a high-speed, high-production wire mesh fence-making apparatus.
Typically, such wire mesh consists of a first plurality of spaced-apart parallel wires called strand wires and a second plurality of parallel wires that diagonally cross and are wrapped around the strand wires. This second plurality of wires is called wrap wires. The second plurality of wires typically consists of two sets, a first set that crosses the strand wires at a first angle and a second set that crosses the strand wires and first set of wrap wires at a second angle such that the first and second set of wrap wires define a diamond-shaped mesh pattern technically known as "Elwood fabric."
In fence-making apparatus according to the prior art, a first set of spools of wire supplying the wrap wires were arranged to rotate around the strand wires and shuttle from strand wire to strand wire in a weaving pattern. A second set of spools supplied the strand wires. The movement of the first set of spools wrapped the wire from the wrap-wire supply around each strand forming a diamond mesh that consisted of parallel strand wires and wrap wires that crossed the strand wires at an angle and wrapped around each one at each crossing point.
In operation, the strand wires are pulled at a predetermined rate from their supply spools through the wrapping area. The rate of speed at which the strand wires were pulled and the shuttling speed of the wrap-wire spools determined the spacing between the adjacent wrap wires and the angle that the wrap wires formed with respect to the strand wires.
According to the prior art, as represented by such patents as U.S. Pat. No. 1,076,831, such fence-making machines used narrow spools which are elongated in the longitudinal direction for containing the wrap wires. The size of the spools was kept narrow in order to enable them to be moved between the relatively closely spaced strand wires without interference. The narrow size of the spools dictated that the spools carried a relatively small quantity of wire, and the fence-making machine had to be stopped frequently to replace empty spools and to insert new spools. Then, before the weaving operation could recommence, the wire from the new spools was welded end-to-end to the strand wires from the old spools. Not only was the fence-making apparatus according to the prior art slow because of the constant replacement of spools and welding of wires, but such fence-making apparatus was characterized by problems caused by the fact that the individual wrap wires were usually twisted in the longitudinal direction. This was due to the fact that the strand-wire spools were vertically oriented and the strand wires were pulled upwardly from the outside of the spools, thereby causing a twist to be imposed on the wrap wires. This led to problems in smooth operation of the machine and inconsistencies in the quality of the wire mesh fabricated thereby.
The production rate of the fence-making apparatus according to the prior art was further inhibited by the start-and-stop nature of the weaving operation. Operation in this fashion was dictated by the fact that the machine would normally be momentarily stopped after the spools of wrap wire had been wrapped around a given strand wire. Stopping of the spools permitted the release of the spool from its operative relation with respect to the strand-wire spindle about which it had just been rotated to permit its transfer to the next adjacent strand spindle. Once the transfer had been accomplished, the machine was restarted to permit translation to and rotation about the new strand wire.